Device for Cooling Electrical Components

ABSTRACT

A device for cooling a plurality of electrical components, each having a component cooling surface to be cooled, includes a first heat sink, a second heat sink, and a plurality of fasteners. The first heat sink has a first heat-sink cooling surface, and the second heat sink has a second heat-sink cooling surface. The first and second heat-sink cooling surfaces are positioned in a planar arrangement such that the first and second heat-sink cooling surfaces face each other. The first heat-sink cooling surface is configured to receive a first sub-set of the component cooling surfaces of the plurality of electrical components, and the second heat-sink cooling surface is configured to receive a second sub-set of the component cooling surfaces. The fasteners are configured to fasten the first and second heat-sink cooling surfaces to the corresponding component cooling surfaces of the plurality of electrical components to be applied.

The invention relates to a device for cooling a multiplicity ofelectrical components. Moreover, the invention relates to a power modulefor controlling an electric drive, and also to an inverter having apower module.

PRIOR ART

Inverters that convert electrical energy from a direct voltage source,for example a battery, into an alternating voltage or alternatingcurrent are conventionally used to operate electric drives. Thealternating voltage is supplied to an electric machine, by way ofexample a synchronous or asynchronous machine. An inverter comprisespower modules that comprise switching elements or semiconductor powerswitches. The prevailing direct voltage is converted into alternatingvoltage by means of a pulse width modulated control of the switchingelements. These switching elements become hot when the inverter is beingoperated. In order to avoid the switching elements overheating and toextend their serviceable life, said switching elements or rather alsothe power modules are cooled.

DE 10 2011 088 218 A1 discloses an electronic power module thatcomprises a cooling element for cooling the switching elements of thepower module so as to cool the semiconductor chips or semiconductorpower switches.

There is a need to reduce the size of such cooling devices and powermodules and to increase their packing density and power density.

DISCLOSURE OF THE INVENTION

A device for cooling a multiplicity of electrical components isprovided, wherein the electrical components each comprise a componentcooling surface that is to be cooled. The device comprises a firstcooling body having a first cooling body cooling surface, and a secondcooling body having a second cooling body cooling surface. The coolingbody cooling surfaces are arranged in a planar manner opposite oneanother. In accordance with the invention, the first cooling bodycooling surface is configured for attaching a first part quantity of thecomponent cooling surfaces of the multiplicity of electrical components.Furthermore, the second cooling body cooling surface is configured forattaching a second part quantity of the component cooling surfaces ofthe multiplicity of electrical components. Furthermore, fastening meansare provided for fastening and pressing the component cooling surfaces,which are to be attached, of the multiplicity of electrical componentsagainst the cooling body cooling surfaces and for creating andmaintaining a heat transfer from the said component cooling surfacesthat are to be attached.

A device for cooling a multiplicity of electrical components isprovided. The electrical components are in particular switching elementsthat are used by way of example to convert a direct voltage into analternating voltage, in other words in particular semiconductor powerswitches. These electrical components that are manufactured inparticular as semiconductor chips from silicon wafers comprise a planarsurface that is suitable as a contact surface for the cooling procedure.Within the scope of this invention, the term ‘component cooling surface’also includes this planar surface of the semiconductor chip. However,the term also includes a layer that is applied where appropriate inaddition to the semiconductor chip. The device in accordance with theinvention comprises a first and a second cooling body that each comprisein turn cooling body cooling surfaces that are arranged in a planarmanner opposite one another. The cooling body cooling surfaces areconfigured in such a manner that it is possible in each case to attach apart quantity of component cooling surfaces of the electricalcomponents. In particular, the first cooling body and the second coolingbody can be a part body of a one piece cooling body, such as also inparticular the cooling body cooling surfaces part surfaces of a onepiece cooling body. Furthermore, fastening means are provided, inparticular mechanical fastening means that render it possible to fastenthe component cooling surfaces to the cooling body cooling surfaces. Thefastening means are configured in such a manner that a heat transferfrom the components into the cooling body is ensured, in that inparticular the component cooling surfaces are pressed against thecooling body cooling surfaces.

Consequently, a device for cooling a multiplicity of electricalcomponents is advantageously provided, said device rendering possible ahigh packing density by virtue of the fact that it is possible to attachthe multiplicity of electrical components to the opposite-lying coolingbody cooling surfaces.

It is provided in another embodiment of the invention that a coolingbody cooling surface is configured as an at least in part planarsurface.

It is thus possible to produce as large as possible surface area contactbetween the component cooling surfaces and the cooling body coolingsurface. Consequently, the transmission of heat between the componentand the cooling body is advantageously optimized.

It is provided in another embodiment of the invention that the first andthe second cooling body cooling surface is configured for attaching apart quantity of the component cooling surfaces of the multiplicity ofelectrical components in such a manner that approximately half of themultiplicity of electrical components that are to be attached can beattached to each of the first and second cooling body cooling surfaces.

In each case, approximately half of the multiplicity of the requiredelectrical components can consequently be attached to the first and thesecond cooling body cooling surface. The cooling body cooling surfacesare arranged in a planar manner lying opposite one another.Consequently, the amount of surface area required is advantageously moreor less halved in comparison to the surface area that would be requiredwhen the components are cooled on one side or rather on one layer.

In another embodiment of the invention, the fastening means areconfigured in the form of a resilient element.

A resilient element can be configured by way of example from a metal ora synthetic material. However, it is also possible to use resilientelements that are configured from other materials, such as by way ofexample fiber composite materials, glass fibers or carbon fibers orceramic compounds. The resilient element can be configured by way ofexample in a spiral shape, a c-shape or in a clamp shape. The use of aresilient element as a fastening means causes the electrical componentsto be pressed against the cooling body. As a result of this pressingarrangement, heat is transmitted from the component to the cooling bodyin an optimum manner. Furthermore, the resilient element is able tobalance with respect to one another and compensate for anytemperature-related stresses and separating out of the materials thatare used within this device.

In another embodiment of the invention, a fastening means is configuredin such a manner that in the form of a resilient element it can besupported on the one hand on a first component surface of an electroniccomponent, said first component surface lying opposite the componentcooling surface, and on the other hand it can be supported on a coolingbody cooling surface that is lying opposite the first component surface,on a second component surface of a further electrical component, saidsecond component surface lying opposite the first component surface, oron a mechanical fixing point that lies opposite the first componentsurface. A fastening means is provided that is configured in the form ofa resilient element, in particular in the form of a spring. Thisfastening means is supported on a first component surface of anelectronic component, said first component surface lying opposite thecomponent cooling surface, wherein in particular the resilient force isdirected to the greatest extent in an orthogonal manner to the componentcooling surface. The face of the fastening means that is lying oppositein the direction of the resilient force is supported either on a coolingbody cooling surface that lies opposite the first component surface oris supported on a second component surface of a further electricalcomponent, said second component surface lying opposite the firstcomponent surface. In the second case, two electronic components areconsequently arranged at least in part one above the other. Furthermore,the fastening means can be supported with the other end that is lyingopposite in the direction of the resilient force on a mechanical fixingpoint that is lying opposite the first component surface. This fixingpoint may be a passive or active element, in particular an electroniccomponent. This fixing point can comprise different, suitable materials,such as by way of example metal, fiber composite material, glass fibersor carbon fibers or ceramic compounds.

In an advantageous manner, variants of how the fastening means can besupported in order to press the component against the cooling body areproposed.

In another embodiment of the invention it is provided that a fasteningmeans is configured in such a manner that it clamps the componentcooling surface of the electronic component and the cooling body coolingsurface against one another or rather pulls said surfaces towards oneanother.

A fastening means is provided that is tensioned by way of example in abow-shaped manner over a component and fixed on both sides of thecomponent to the cooling body. In an advantageous manner, a fasteningmeans is consequently provided that does not require mechanical supporton a surface that is lying opposite the cooling body cooling surface.

In a further embodiment of the invention, it is provided that afastening means comprises a screw or a rivet. The component may be fixedto the cooling body by way of example by means of a screw or a rivet.The fastening means may also be fixed to a cooling body or the coolingbody cooling surface by way of example by means of a screw or a rivet.In an advantageous manner, variants are provided that ensure that thefastening means is fixed in a reliable and secure manner.

In another embodiment of the invention, it is provided that the coolingbody cooling surfaces are configured for attaching a part of thecomponent cooling surfaces of the multiplicity of electrical componentsin such a manner that electrical components can be attached positionedadjacent to one another along a straight line in one plane, wherein acomponent cooling surface of a first electrical component can beattached to the first cooling body cooling surface and alternately acomponent cooling surface of a further electrical component can beattached to the second cooling body cooling surface. By virtue ofattaching the electrical components in this alternating manner to theupper and the lower cooling body cooling surface, this means that thecooling body cooling surface comprises part regions that are notattached to an electrical component. In an advantageous manner, thisconsequently provides the cooling body with a comparatively highercooling capacity.

In another embodiment of the invention, it is provided that the coolingbody cooling surfaces are configured for attaching a part quantity ofcomponent cooling surfaces of the multiplicity of electrical componentsin such a manner that a first and a second electrical component can beattached in two planes one above the other, wherein a component coolingsurface of the first electrical component can be attached to the coolingbody cooling surface of the first cooling body, and a component coolingsurface of a second electrical component can be attached to the coolingbody cooling surface of the second cooling body.

This means that the components are arranged one above the other. One ofthe components is cooled in the direction of the first cooling body, anda second component is cooled in the direction of the second coolingbody. This arrangement of the components and the cooling bodies withrespect to one another produces a particularly high packing density ofthe components.

Moreover, a power module is provided for controlling an electric drive.The power module comprises a device as described above for cooling theattached multiplicity of electrical components, in particular switchingelements and/or semiconductor power switches. A power module is providedthat in addition to the multiplicity of electrical components comprisesa device as described above for cooling the electrical components. In anadvantageous manner, a power module that comprises a high packingdensity and power density is provided.

Moreover, an inverter is provided that comprises a power module asdescribed above. In an advantageous manner, an inverter that comprises ahigh packing density and power density is provided.

It is understood that the features, characteristics and advantages ofthe device in accordance with the invention relate accordingly to thepower module or the inverter and conversely or can be used therewith.

Further features and advantages of the embodiments of the invention aredisclosed in the following description with reference to the attacheddrawings.

SHORT DESCRIPTION OF THE DRAWING

The invention is to be further explained in the following with referenceto some figures, in which:

FIG. 1 illustrates schematically a device for cooling a multiplicity ofelectrical components in a schematic view,

FIG. 2 likewise illustrates schematically a device for cooling amultiplicity of electrical components,

FIG. 3 illustrates a fastening means that is fixed to a cooling body,

FIG. 4 illustrates an inverter having a power module for supplying anelectric machine.

EMBODIMENTS OF THE INVENTION

FIG. 1 illustrates schematically a device 100 or a section of a powermodule, comprising a first cooling body K1 having a first cooling bodycooling surface KF1, and a second cooling body K2 having a secondcooling body cooling surface KF2 that is arranged lying opposite andspaced apart in a planar manner to the first cooling body coolingsurface KF1. Furthermore, a multiplicity of electrical components BE1,BE2 . . . BEn is illustrated in an exemplary manner. The individualcomponents comprise in each case a component cooling surface BEK1, BEK2. . . BEKn. Furthermore, fastening means BM1, BM2 . . . BMn areillustrated that are supported on the one hand on the component surfacesBEF1, BEF2 . . . BEFn of the multiplicity of electrical components, saidcomponent surfaces being arranged opposite the component coolingsurfaces BEK1, BEK2 . . . BEKn, and supported on the other hand on theopposite-lying cooling body cooling surface KF1, KF2.

FIG. 2 illustrates schematically a similar construction of the coolingbody K1, K2 and the associated cooling body cooling surfaces KF1 andKF2, and opposite-lying components BE1, BE3 or respectively BE4, BE2.The illustrated fastening means BM1, BM2, BM3, BM4 are supported on theone hand on the first component surface BEF1, BEF2, BEF3, BEF4 of theelectronic components BE1, BE2, BE3, BE4, said first component surfacelying opposite the component cooling surface BEK1, BEK2, BEK3, BEK4, andsupported on the other hand on the second component surface, BEF1, BEF2,BEF3, BEF4 of a further electrical component, said second componentsurface lying opposite the first component surface BEF1, BEF2, BEF3,BEF4. Furthermore, a fastening means BMn is illustrated that issupported on the one hand on a first component surface BEFn of theelectronic component BEn, said first component surface lying oppositethe component element cooling surface BEKn, and on a mechanical fixingpoint MF that lies opposite the first component surface BEFn. It is alsopossible to support opposite-lying fastening means, such as by way ofexample BM1 and BM3, against one another between the components.Alternatively, two opposite-lying fastening means, such as by way ofexample BM2 and BM4, may also be configured in one piece as a commonfastening means.

FIG. 3 illustrates a cooling body K1, K2 having a cooling body coolingsurface KF1, KF2 and a component BE1 that is attached thereto andcomprises a component cooling surface BEK1, wherein a fastening meansBM1 in the form of a resilient clamp is illustrated around the componentBE1 that is fixed by means of a screw or a rivet to the cooling body K1,K2.

FIG. 4 illustrates a schematic view of an inverter WR that comprises atleast one power module LM that is used to control an electric machineEM.

1. A device for cooling a plurality of electrical components eachcomponent having a cooling component cooling surface, the devicecomprising: a first cooling body including a first cooling body coolingsurface configured receive a first sub-set of the component coolingsurfaces of the plurality of electrical components; and a second coolingbody including a second cooling body cooling surface, the second coolingbody positioned in a planar arrangement with the first cooling body suchthat the first cooling body cooling surface and the second cooling bodycooling surface are opposite each other, and the second cooling bodycooling surface configured to receive a second sub-set of the componentcooling surfaces of the plurality of electrical components; and afastening mechanism configured to fasten the first and second sub-setsof the component cooling surfaces to the first and second cooling bodycooling surfaces, respectively.
 2. The device as claimed in claim 1,wherein at least one of the first and second cooling body coolingsurfaces is as a planar surface, at least in part.
 3. The device asclaimed in claim 1, wherein the first and second cooling body coolingsurfaces are configured to receive approximately half of the pluralityof electrical components.
 4. The device as claimed in claim 1, whereinfastening mechanism includes a resilient element.
 5. The device asclaimed in claim 3, wherein the fastening mechanism is configured suchthat in a fastened position, the fastening mechanism is: supported on afirst component surface of an electronic component, the first componentsurface lying opposite the first and second component cooling surfaces;supported on a one of the cooling body cooling surfaces that is lyingopposite the first component element; supported on a second componentsurface of a further electrical component, the second component surfacelying opposite the first component surface; or supported on a mechanicalfixing point that lies opposite the first component surface.
 6. Thedevice as claimed in claim 1, wherein the fastening mechanism is furtherconfigured in to clamp the first and second sub-sets of componentcooling surface of the electronic component and the first and secondcooling body cooling surface against each other, respectively.
 7. Thedevice as claimed in claim 1, wherein the fastening mechanism includes ascrew or a rivet.
 8. The device as claimed in claim 1, wherein each ofthe first and second the cooling body cooling surfaces is furtherconfigured to receive the first and second sub-sets of component coolingsurfaces of the plurality of electrical components, respectively, inpositions such that the electrical components on each of the first andsecond cooling body surfaces are positioned adjacent to each other alonga straight line in one plane, and such that a component cooling surfaceof a first electrical component is attached to the first cooling bodycooling surface and a component cooling surface of a further electricalcomponent is attached to the second cooling body cooling surface.
 9. Thedevice as claimed in claim 1, wherein each of the first and second thecooling body cooling surfaces is further configured to receive the firstand second sub-sets of component cooling surfaces of the plurality ofelectrical components, respectively, in positions such that a first anda second electrical component are attached to the device in two planesone above the other, and such that a component cooling surface of thefirst electrical component is attached to the cooling body coolingsurface of the first cooling body and a component cooling surface of thesecond electrical component is attached to the cooling body coolingsurface of the second cooling body.
 10. A power module for controllingan electric drive, comprising: a plurality of electrical components,each component including a cooling component cooling surface; and adevice attached to the plurality of electrical components and configuredto cool the attached plurality of electrical components, the deviceincluding: a first cooling body having a first cooling body coolingsurface configured receive a first sub-set of the component coolingsurfaces of the plurality of electrical components; and a second coolingbody having a second cooling body cooling surface, the second coolingbody positioned in a planar arrangement with the first cooling body suchthat the first cooling body cooling surface and the second cooling bodycooling surface are opposite each other, and the second cooling bodycooling surface configured to receive a second sub-set of the componentcooling surfaces of the plurality of electrical components; and afastening mechanism configured to fasten the first and second sub-setsof the component cooling surfaces to the first and second cooling bodycooling surfaces, respectively.
 11. An inverter comprising: a powermodule that includes: a plurality of electrical components, eachcomponent including a cooling component cooling surface; and a deviceattached to the plurality of electrical components and configured tocool the attached plurality of electrical components, the deviceincluding: a first cooling body having a first cooling body coolingsurface configured receive a first sub-set of the component coolingsurfaces of the plurality of electrical components; and a second coolingbody having a second cooling body cooling surface, the second coolingbody positioned in a planar arrangement with the first cooling body suchthat the first cooling body cooling surface and the second cooling bodycooling surface are opposite each other, and the second cooling bodycooling surface configured to receive a second sub-set of the componentcooling surfaces of the plurality of electrical components; and afastening mechanism configured to fasten the first and second sub-setsof the component cooling surfaces to the first and second cooling bodycooling surfaces, respectively.
 12. The power module according to claim10, wherein the plurality of electrical components includes at least oneof a switching element and a semiconductor power switch.
 13. Theinverter according to claim 11, wherein the plurality of electricalcomponents includes at least one of a switching element and asemiconductor power switch.